/*
 * 模块名称：ST7735S LCD驱动
 * 模块功能：提供128x160 RGB TFT屏幕的初始化、画点、画线、填充、显示字符串等功能
 * 适用平台：STM32F103C8T6 + SPI2
 * 作者：王建锋
 * 创建日期：2026-07-13
 * 修改记录：
 *     2026-07-13  王建锋  创建初始版本
 */

#include "st7735s.h"
#include "lcd_data.h"
#include "spi.h"
#include <stdio.h>
#include <string.h>

static uint16_t s_lcd_width = LCD_WIDTH;
static uint16_t s_lcd_height = LCD_HEIGHT;

extern DMA_HandleTypeDef hdma_spi2_tx;

/* 8x16 ASCII字体（ASCII 32-126），每字符16字节 - 定义在 lcd_data.c 中 */

/*
 * 函数功能：软件SPI写一个字节
 * 入口参数：data - 要发送的数据
 * 返回值：无
 * 函数说明：模拟SPI时序发送一个字节，MSB先
 */
static void st7735s_spi_write_byte(uint8_t data)
{
    uint8_t i;

    for (i = 0; i < 8; i++) {
        HAL_GPIO_WritePin(LCD_SCL_PORT, LCD_SCL_PIN, GPIO_PIN_RESET);
        if (data & 0x80) {
            HAL_GPIO_WritePin(LCD_SDA_PORT, LCD_SDA_PIN, GPIO_PIN_SET);
        } else {
            HAL_GPIO_WritePin(LCD_SDA_PORT, LCD_SDA_PIN, GPIO_PIN_RESET);
        }
        __NOP();
        __NOP();
        HAL_GPIO_WritePin(LCD_SCL_PORT, LCD_SCL_PIN, GPIO_PIN_SET);
        __NOP();
        __NOP();
        data <<= 1;
    }
}

/*
 * 函数功能：写入命令
 * 入口参数：cmd - 命令字节
 * 返回值：无
 * 函数说明：拉低DC，选择芯片，发送命令，释放芯片
 */
static void st7735s_write_cmd(uint8_t cmd)
{
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_RESET);
    st7735s_spi_write_byte(cmd);
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：写入数据
 * 入口参数：data - 数据字节
 * 返回值：无
 * 函数说明：拉高DC，选择芯片，发送数据，释放芯片
 */
static void st7735s_write_data(uint8_t data)
{
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_SET);
    st7735s_spi_write_byte(data);
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：写入多字节数据（CS保持低）
 * 入口参数：p_data - 数据缓冲区指针
 *           len    - 字节数
 * 返回值：无
 * 函数说明：用于连续写入多个数据字节，省去中间CS跳变
 */
static void st7735s_write_data_multi(const uint8_t *p_data, uint16_t len)
{
    uint16_t i;

    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_SET);
    for (i = 0; i < len; i++) {
        st7735s_spi_write_byte(p_data[i]);
    }
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：写入16位颜色数据
 * 入口参数：p_color - 16位颜色缓冲区指针
 *           len - 像素个数
 * 返回值：无
 * 函数说明：MSB先发送RGB565数据
 */
static void st7735s_write_colors(uint16_t *p_color, uint16_t len)
{
    uint16_t i;

    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_RESET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_SET);
    for (i = 0; i < len; i++) {
        st7735s_spi_write_byte((uint8_t)(p_color[i] >> 8));
        st7735s_spi_write_byte((uint8_t)(p_color[i] & 0xFF));
    }
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
}

/*
 * 函数功能：LCD初始化
 * 入口参数：无
 * 返回值：无
 * 函数说明：执行ST7735S标准初始化序列
 */
void st7735s_init(void)
{
    GPIO_InitTypeDef GPIO_InitStruct = {0};

    printf("LCD init start (soft SPI)...\r\n");

    /* 将SCL和SDA引脚切换为GPIO输出（软件SPI） */
    GPIO_InitStruct.Pin = LCD_SCL_PIN | LCD_SDA_PIN;
    GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
    GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
    HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);

    HAL_GPIO_WritePin(LCD_SCL_PORT, LCD_SCL_PIN, GPIO_PIN_SET);
    HAL_GPIO_WritePin(LCD_SDA_PORT, LCD_SDA_PIN, GPIO_PIN_SET);

    /* 确保CS和RST初始为高，避免LCD在初始化期间被错误选中 */
    HAL_GPIO_WritePin(LCD_CS_PORT, LCD_CS_PIN, GPIO_PIN_SET);
    HAL_GPIO_WritePin(LCD_RST_PORT, LCD_RST_PIN, GPIO_PIN_SET);
    HAL_GPIO_WritePin(LCD_DC_PORT, LCD_DC_PIN, GPIO_PIN_RESET);
    HAL_Delay(10);

    printf("IO: RST=%d DC=%d CS=%d\r\n",
           (int)HAL_GPIO_ReadPin(LCD_RST_PORT, LCD_RST_PIN),
           (int)HAL_GPIO_ReadPin(LCD_DC_PORT, LCD_DC_PIN),
           (int)HAL_GPIO_ReadPin(LCD_CS_PORT, LCD_CS_PIN));

    /* 硬件复位 */
    printf("HW reset...\r\n");
    HAL_GPIO_WritePin(LCD_RST_PORT, LCD_RST_PIN, GPIO_PIN_RESET);
    HAL_Delay(10);
    HAL_GPIO_WritePin(LCD_RST_PORT, LCD_RST_PIN, GPIO_PIN_SET);
    HAL_Delay(120);

    /* 软件复位 */
    printf("SW reset...\r\n");
    st7735s_write_cmd(LCD_CMD_SWRESET);
    HAL_Delay(150);

    /* 退出睡眠模式 */
    printf("Sleep out...\r\n");
    st7735s_write_cmd(LCD_CMD_SLPOUT);
    HAL_Delay(500);

    /* 帧率控制 */
    printf("Frame rate...\r\n");
    st7735s_write_cmd(LCD_CMD_FRMCTR1);
    st7735s_write_data(0x01);
    st7735s_write_data(0x2C);
    st7735s_write_data(0x2D);

    st7735s_write_cmd(LCD_CMD_FRMCTR2);
    st7735s_write_data(0x01);
    st7735s_write_data(0x2C);
    st7735s_write_data(0x2D);

    st7735s_write_cmd(LCD_CMD_FRMCTR3);
    st7735s_write_data(0x01);
    st7735s_write_data(0x2C);
    st7735s_write_data(0x2D);
    st7735s_write_data(0x01);
    st7735s_write_data(0x2C);
    st7735s_write_data(0x2D);

    /* 显示反转控制 */
    st7735s_write_cmd(LCD_CMD_INVCTR);
    st7735s_write_data(0x07);

    /* 功率控制 */
    printf("Power ctrl...\r\n");
    st7735s_write_cmd(LCD_CMD_PWCTR1);
    st7735s_write_data(0xA2);
    st7735s_write_data(0x02);
    st7735s_write_data(0x84);

    st7735s_write_cmd(LCD_CMD_PWCTR2);
    st7735s_write_data(0xC5);

    st7735s_write_cmd(LCD_CMD_PWCTR3);
    st7735s_write_data(0x0A);
    st7735s_write_data(0x00);

    st7735s_write_cmd(LCD_CMD_PWCTR4);
    st7735s_write_data(0x8A);
    st7735s_write_data(0x2A);

    st7735s_write_cmd(LCD_CMD_PWCTR5);
    st7735s_write_data(0x8A);
    st7735s_write_data(0xEE);

    /* VCOM控制 */
    st7735s_write_cmd(LCD_CMD_VMCTR1);
    st7735s_write_data(0x0E);

    /* 竖屏模式 */
    printf("MADCTL...\r\n");
    st7735s_write_cmd(LCD_CMD_MADCTL);
    st7735s_write_data(0xC8);

    /* 像素格式: 16位RGB565 */
    printf("COLMOD...\r\n");
    st7735s_write_cmd(LCD_CMD_COLMOD);
    st7735s_write_data(0x05);

    /* Gamma校正 */
    printf("Gamma...\r\n");
    st7735s_write_cmd(LCD_CMD_GMCTRP1);
    st7735s_write_data(0x02);
    st7735s_write_data(0x1C);
    st7735s_write_data(0x07);
    st7735s_write_data(0x12);
    st7735s_write_data(0x37);
    st7735s_write_data(0x32);
    st7735s_write_data(0x29);
    st7735s_write_data(0x2D);
    st7735s_write_data(0x29);
    st7735s_write_data(0x25);
    st7735s_write_data(0x2B);
    st7735s_write_data(0x39);
    st7735s_write_data(0x00);
    st7735s_write_data(0x01);
    st7735s_write_data(0x03);
    st7735s_write_data(0x10);

    st7735s_write_cmd(LCD_CMD_GMCTRN1);
    st7735s_write_data(0x03);
    st7735s_write_data(0x1D);
    st7735s_write_data(0x07);
    st7735s_write_data(0x06);
    st7735s_write_data(0x2E);
    st7735s_write_data(0x2C);
    st7735s_write_data(0x29);
    st7735s_write_data(0x2D);
    st7735s_write_data(0x2E);
    st7735s_write_data(0x2E);
    st7735s_write_data(0x37);
    st7735s_write_data(0x3F);
    st7735s_write_data(0x00);
    st7735s_write_data(0x00);
    st7735s_write_data(0x02);
    st7735s_write_data(0x10);

    /* 关闭反转 */
    st7735s_write_cmd(0x20);

    /* 进入正常显示模式（关键！） */
    printf("NORON...\r\n");
    st7735s_write_cmd(0x13);
    HAL_Delay(10);

    /* 开启显示 */
    printf("DISPON...\r\n");
    st7735s_write_cmd(LCD_CMD_DISPON);
    HAL_Delay(100);
    printf("LCD init done\r\n");
}

/*
 * 函数功能：设置显示窗口
 * 入口参数：x1 - 起始列
 *           y1 - 起始行
 *           x2 - 结束列
 *           y2 - 结束行
 * 返回值：无
 * 函数说明：设置后续写入操作的窗口区域
 */
void st7735s_set_window(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2)
{
    st7735s_write_cmd(LCD_CMD_CASET);
    st7735s_write_data(0x00);
    st7735s_write_data((uint8_t)x1);
    st7735s_write_data(0x00);
    st7735s_write_data((uint8_t)x2);

    st7735s_write_cmd(LCD_CMD_RASET);
    st7735s_write_data(0x00);
    st7735s_write_data((uint8_t)y1);
    st7735s_write_data(0x00);
    st7735s_write_data((uint8_t)y2);

    st7735s_write_cmd(LCD_CMD_RAMWR);
}

/*
 * 函数功能：填充矩形区域
 * 入口参数：x1 - 起始列
 *           y1 - 起始行
 *           x2 - 结束列
 *           y2 - 结束行
 *           color - 填充颜色 (RGB565)
 * 返回值：无
 * 函数说明：用指定颜色填充矩形区域
 */
void st7735s_fill_rect(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t color)
{
    uint32_t pixel_count;
    uint16_t i;
    uint16_t buf[64];

    if (x1 > x2) {
        uint16_t t = x1;
        x1 = x2;
        x2 = t;
    }
    if (y1 > y2) {
        uint16_t t = y1;
        y1 = y2;
        y2 = t;
    }

    pixel_count = (uint32_t)(x2 - x1 + 1) * (y2 - y1 + 1);

    /* 预填充颜色缓冲区 */
    for (i = 0; i < 64; i++) {
        buf[i] = color;
    }

    st7735s_set_window(x1, y1, x2, y2);

    /* 分块发送 */
    while (pixel_count >= 64) {
        st7735s_write_colors(buf, 64);
        pixel_count -= 64;
    }
    if (pixel_count > 0) {
        st7735s_write_colors(buf, (uint16_t)pixel_count);
    }
}

/*
 * 函数功能：全屏填充
 * 入口参数：color - 填充颜色 (RGB565)
 * 返回值：无
 * 函数说明：用指定颜色填充整个屏幕
 */
void st7735s_fill_screen(uint16_t color)
{
    printf("fill_screen 0x%04X\r\n", color);
    st7735s_fill_rect(0, 0, s_lcd_width - 1, s_lcd_height - 1, color);
}

/*
 * 函数功能：画点
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           color - 颜色 (RGB565)
 * 返回值：无
 * 函数说明：在指定位置画一个点
 */
void st7735s_draw_pixel(uint16_t x, uint16_t y, uint16_t color)
{
    if (x >= s_lcd_width || y >= s_lcd_height) {
        return;
    }
    st7735s_set_window(x, y, x, y);
    st7735s_write_data((uint8_t)(color >> 8));
    st7735s_write_data((uint8_t)color);
}

/*
 * 函数功能：画线
 * 入口参数：x1 - 起始列
 *           y1 - 起始行
 *           x2 - 结束列
 *           y2 - 结束行
 *           color - 颜色 (RGB565)
 * 返回值：无
 * 函数说明：画一条直线（Bresenham算法）
 */
void st7735s_draw_line(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2, uint16_t color)
{
    int16_t dx;
    int16_t dy;
    int16_t sx;
    int16_t sy;
    int16_t err;
    int16_t e2;
    uint16_t x;
    uint16_t y;

    if (x1 == x2) {
        /* 垂直线 */
        if (y1 > y2) {
            y = y1;
            y1 = y2;
            y2 = y;
        }
        st7735s_fill_rect(x1, y1, x1, y2, color);
        return;
    }

    if (y1 == y2) {
        /* 水平线 */
        if (x1 > x2) {
            x = x1;
            x1 = x2;
            x2 = x;
        }
        st7735s_fill_rect(x1, y1, x2, y1, color);
        return;
    }

    dx = (int16_t)x2 - (int16_t)x1;
    if (dx < 0) {
        dx = -dx;
    }
    sx = x1 < x2 ? 1 : -1;
    dy = (int16_t)y2 - (int16_t)y1;
    if (dy < 0) {
        dy = -dy;
    }
    sy = y1 < y2 ? 1 : -1;
    err = (dx > dy ? dx : -dy) / 2;

    x = x1;
    y = y1;

    while (1) {
        st7735s_draw_pixel(x, y, color);
        if (x == x2 && y == y2) {
            break;
        }
        e2 = err;
        if (e2 > -dx) {
            err -= dy;
            x += sx;
        }
        if (e2 < dy) {
            err += dx;
            y += sy;
        }
    }
}

/*
 * 函数功能：画矩形
 * 入口参数：x - 左上角列
 *           y - 左上角行
 *           width - 宽度
 *           height - 高度
 *           color - 颜色 (RGB565)
 * 返回值：无
 * 函数说明：画一个空心矩形
 */
void st7735s_draw_rect(uint16_t x, uint16_t y, uint16_t width, uint16_t height, uint16_t color)
{
    st7735s_draw_line(x, y, x + width - 1, y, color);
    st7735s_draw_line(x, y + height - 1, x + width - 1, y + height - 1, color);
    st7735s_draw_line(x, y, x, y + height - 1, color);
    st7735s_draw_line(x + width - 1, y, x + width - 1, y + height - 1, color);
}

/*
 * 函数功能：画圆
 * 入口参数：x0 - 圆心列
 *           y0 - 圆心行
 *           radius - 半径
 *           color - 颜色 (RGB565)
 * 返回值：无
 * 函数说明：画一个空心圆（Bresenham算法）
 */
void st7735s_draw_circle(uint16_t x0, uint16_t y0, uint16_t radius, uint16_t color)
{
    int16_t f = 1 - radius;
    int16_t ddf_x = 1;
    int16_t ddf_y = -2 * radius;
    int16_t x = 0;
    int16_t y = radius;

    st7735s_draw_pixel(x0, y0 + radius, color);
    st7735s_draw_pixel(x0, y0 - radius, color);
    st7735s_draw_pixel(x0 + radius, y0, color);
    st7735s_draw_pixel(x0 - radius, y0, color);

    while (x < y) {
        if (f >= 0) {
            y--;
            ddf_y += 2;
            f += ddf_y;
        }
        x++;
        ddf_x += 2;
        f += ddf_x;

        st7735s_draw_pixel(x0 + x, y0 + y, color);
        st7735s_draw_pixel(x0 - x, y0 + y, color);
        st7735s_draw_pixel(x0 + x, y0 - y, color);
        st7735s_draw_pixel(x0 - x, y0 - y, color);
        st7735s_draw_pixel(x0 + y, y0 + x, color);
        st7735s_draw_pixel(x0 - y, y0 + x, color);
        st7735s_draw_pixel(x0 + y, y0 - x, color);
        st7735s_draw_pixel(x0 - y, y0 - x, color);
    }
}

/*
 * 函数功能：显示字符
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           ch - 字符 (ASCII 32-126)
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：在指定位置显示一个8x16 ASCII字符
 */
void st7735s_draw_char(uint16_t x, uint16_t y, char ch, uint16_t color, uint16_t bg_color)
{
    uint16_t i;
    uint16_t j;
    uint8_t line;

    if (ch < 32 || ch > 126) {
        ch = ' ';
    }

    for (i = 0; i < 16; i++) {
        line = LCD_F8x16[ch - 32][i];
        for (j = 0; j < 8; j++) {
            if (line & 0x80) {
                st7735s_draw_pixel(x + j, y + i, color);
            } else {
                st7735s_draw_pixel(x + j, y + i, bg_color);
            }
            line <<= 1;
        }
    }
}

/*
 * 函数功能：显示字符串
 * 入口参数：x - 列坐标
 *           y - 行坐标
 *           str - 字符串指针
 *           color - 字符颜色 (RGB565)
 *           bg_color - 背景颜色 (RGB565)
 * 返回值：无
 * 函数说明：在指定位置显示字符串
 */
void st7735s_draw_string(uint16_t x, uint16_t y, const char *str, uint16_t color, uint16_t bg_color)
{
    while (*str) {
        if (x + 8 > s_lcd_width) {
            x = 0;
            y += 16;
        }
        if (y + 16 > s_lcd_height) {
            break;
        }
        st7735s_draw_char(x, y, *str, color, bg_color);
        x += FONT_WIDTH_8;
        str++;
    }
}

/*
 * 函数功能：设置屏幕方向
 * 入口参数：rotation - 方向 (0-3)
 * 返回值：无
 * 函数说明：0:竖屏 1:横屏 2:竖屏反转 3:横屏反转
 */
void st7735s_set_rotation(uint8_t rotation)
{
    st7735s_write_cmd(LCD_CMD_MADCTL);
    switch (rotation) {
    case 0:
        st7735s_write_data(0xC8);
        s_lcd_width = 128;
        s_lcd_height = 160;
        break;
    case 1:
        st7735s_write_data(0x78);
        s_lcd_width = 160;
        s_lcd_height = 128;
        break;
    case 2:
        st7735s_write_data(0x08);
        s_lcd_width = 128;
        s_lcd_height = 160;
        break;
    case 3:
        st7735s_write_data(0xA8);
        s_lcd_width = 160;
        s_lcd_height = 128;
        break;
    default:
        break;
    }
}

/*
 * 函数功能：设置背光
 * 入口参数：state - 1:开  0:关
 * 返回值：无
 * 函数说明：控制LCD背光（如有硬件背光控制）
 */
void st7735s_backlight(uint8_t state)
{
    (void)state;
    /* 当前硬件未连接背光控制引脚，预留接口 */
}